The wind-hydro system includes a wind farm, a hydroelectric power plant, a pumping station and two water tanks.
The wind farm has five wind turbines and 11.5 MW of installed power (5 x 2.3 MW). To give you an idea, a household consumes 4,000 KWh a year. This means that Gorona del Viento can already supply electricity to 5,000 families .When the project will be completed, it will power the entire population of the island.
In addition to supplying households with electricity, the wind turbines supply energy to several pumping stations to retain water in a raised tank.
The water in this tank is a way of storing energy as it slides towards the lowest part of the island by the force of gravity, powering the hydroelectric plant.
The hydroelectric power plant has a power of 11.3 MW (4 x 2.83 MW) and the pumping station 6 MW (2 x 1.5 MW + 6 x 0.5 MW).
The lower tank can hold 150,000 m3 of water and the top tank, which is built in a natural volcanic basin, can store 380,000 m3.
In August 2015, thanks to the wind-hydro power station, the people of El Hierro were able to meet their goal: self-sufficiency in electricity without using fossil fuels. On August 9th, at noon, the Gorona del Viento power plant generated all the island's electricity using renewable energy for four consecutive hours. Over the following months, the island's 100% renewable generation period has been extended, becoming a world pioneer.
“Currently the wind-hydro power plant is capable of covering 75% of annual electricity demand with renewable sources. This percentage will keep on growing if we now work on adapting this demand to the efficient model using alternative energies that El Hierro has laid out in its 100% Renewable Project”
This system is expected to provide annual savings of 18,700 tonnes of CO2 emissions and €2 million ,equivalent to the 5,000 tonnes of diesel fuel that no longer needs to be bought. Add to this the reduction in emissions and consumption from the electric vehicles considered in the plan to develop this new technology on the island.
The effectiveness of this project improves with each passing year, and in the first half of 2018 the island’s power station generated 100% of the island’s electricity needs for a period of 1,450 hours, a percentage notably higher than that for 2017, which achieved this level for a period of 892 hours. In addition to this, during the first six months of the year savings were made of 3,700 tonnes of diesel oil, and of approximately 12,100 tonnes of CO2 emissions.
The Gorona del Viento wind-hydro power plant now manages to produce all the energy that the island needs, with an annual average of 60% of energy from renewables, often hitting peaks of 100%.